Answer to Question #232267 in Physics for zyyy

Question

a constant force acts on a 5.0kg object and reduces its velocity from 7.0 m/s to 3.0 m/s in a time of 3.0 s. Find the force

Answer 1

Given:

$m=5.0\:\rm kg$

$v_i=7.0\:\rm m/s$

$v_f=3.0\:\rm m/s$

$\Delta t=3.0\:\rm s$

The acceleration of an object

$$a=\frac{\Delta v}{\Delta t}=\frac{3.0-7.0}{3.0}=-1.3\:\rm m/s^2$$

The magnitude of force

$$F=ma=5.0*1.3=6.7\:\rm N$$